1. Field of the Invention
The present invention relates to a connector structure of an internal combustion engine ignition device causing an ignition plug of the internal combustion engine to make a spark discharge.
2. Description of the Related Art
Conventionally, as an internal combustion engine ignition coil, there is the one that comprises a primary connector including a low voltage terminal for providing the electrical connection between a primary coil and a switching module integrally at a part of an insulating case as shown in, for example, the Japanese Laid-open Utility Model Publication No. 31134/1994 (Paragraph [0003]).
In a connector of an internal combustion engine ignition coil, there are several numbers of external connection terminals requiring no noble metal coat for a transformer, and external connection terminals requiring the noble metal coat for a control circuit section. These external connection terminals are manufactured by press working into a single piece with the use of a material 200 to be pressed as shown in FIG. 9. That is, in the material 200 to be pressed, a striped pattern of noble metal coat (hatched part 201) has preliminarily been applied to a terminal area 200a requiring the electrical contact function in the internal part of the connector. As a result, the same striped pattern of noble metal coat is applied to the external connection terminals requiring no noble metal coat.
In addition, unnecessary parts that are not used as a product after the press working are thrown away as scraps; and the cost of noble meta coat onto the above-mentioned scraps around the external connection terminals requiring no noble metal coat is added to material costs. As a result, higher costs of the product will be induced.
Further, since a noble metal coat is applied to all the external connection terminals in the connector, groping of external connection terminals through which a large current and a small current are carried is not always definite. Thus, there are some cases in which a group of external connection terminals through which a large current is carried are disposed adjacent to each other, and there is a problem of causing short circuit fault between the external connection terminals through which a large current is carried in the small connector.